Behind every great mayor, there's a child. Or so these two spirited children's novels will have us believe. Politics, it seems, is now the domain of the pint-size.

In ''I Am Rubber, You Are Glue,'' when Bart Barton learns his father is running for mayor, he sees the campaign as a springboard for himself, as well. It's going to launch him into high visibility, the spectacular popularity that's eluded him in Little League and the classroom. Bart's whole problem, though, is his high visibility. A showoff who menaces relatives with knock-knock jokes, Bart is always clamoring for attention. Only his zany, off-center humor saves him.

During the year his father runs for mayor, Bart's extravagant promotional ploys bring havoc to the campaign. Yet, Yn the end, he not only helps his father win, but, most important, learns what really causes people to take notice: quiet self-esteem.

Jane Morton's novel rings true from start to finish. I only wish this slim book, so packed with zany episodes were longer.

In ''My Mother the Mayor, Maybe,'' we have the mirror reverse in plot. Here, 10-year-old B.J. Pinkerton helps her mother run for mayor, a post held by the same man for the last 18 years. Which issue should B.J. tackle first: that her mother is the first woman to run for mayor, or that she's one of the few Democrats in Republican Cranberry Falls? Her mother solves the problem by focusing on the real issue: proposed power lines that would cut right through the town, razing people's houses and slicing off part of the state park.

In the campaign's eight weeks, B.J. learns a lot about politics -- at home and in the community. At home, meals -- now invariably hot dogs -- are prepared by B.J.'s sister. At school, roles also shift when friends choose political sides. But, in the end, B.J. learns that, while the law sanctions behavior which is less than honorable, the desire to do right is rewarded.